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In 1914, the Annals of the Missouri Botanical Garden, the
flagship journal of the scientific publications program, was founded
to contain research contributions from staff members at the Garden,
graduate students of the Henry Shaw School of Botany of Washington
University, and from visiting botanists associated with the Garden.
Since that time, the Annals has grown to be one of the world's
premiere peer-reviewed botanical journals, published quarterly,
with an emphasis on systematic botany and taxonomy. Articles are
accepted in English and Spanish, from botanists at the Garden and
from the international botanical community.

The "moving wall" represents the time period between the last issue
available in JSTOR and the most recently published issue of a journal.
Moving walls are generally represented in years. In rare instances, a
publisher has elected to have a "zero" moving wall, so their current
issues are available in JSTOR shortly after publication.
Note: In calculating the moving wall, the current year is not counted.
For example, if the current year is 2008 and a journal has a 5 year
moving wall, articles from the year 2002 are available.

Terms Related to the Moving Wall

Fixed walls: Journals with no new volumes being added to the archive.

Absorbed: Journals that are combined with another title.

Complete: Journals that are no longer published or that have been
combined with another title.

Abstract

Parsimony analyses were conducted for 223 species representing all major groups of angiosperms using entire 18S ribosomal DNA (rDNA) sequences. Although no search swapped to completion, the topologies recovered are highly concordant with those retrieved via broad analyses based on the chloroplast gene rbcL. The general congruence of 18S rDNA and rbcL topologies further clarifies the broad picture of angiosperm phylogeny. In all analyses, the first-branching angiosperms are Amborellaceae, Austrobaileyaceae, Illiciaceae, and Schisandraceae, all woody magnoliids. These taxa are always followed by the paleoherb family Nymphaeaceae. This same general order of early-branching taxa is preserved with several suites of outgroups. In most searches, the remaining early-branching taxa represent Piperales and other orders of subclass Magnoliidae (sensu Cronquist). With the exception of Acorus, the monocots are supported as monophyletic and typically have as their sister Ceratophyllum. In most analyses, taxa with uniaperturate pollen form a grade at the base of the angiosperms; a large eudicot clade is composed primarily of taxa having triaperturate pollen. Two large subclades are present within the eudicots, one consisting largely of Rosidae and a second corresponding closely to Asteridae sensu lato. Subclasses Dilleniidae and Hamamelidae are highly polyphyletic. These data sets of 18S rDNA sequences also permit an analysis of the patterns of molecular evolution of this gene. Problems deriving from both the prevalence of indels and uncertain alignment of 18S rDNA sequences have been overstated in previous studies. With the exception of a few well-defined regions, insertions and deletions are relatively uncommon in 18S rDNA; sequences are therefore easily aligned by eye across the angiosperms. Indeed, several indels in highly conserved regions appear to be phylogenetically informative. Initial analyses suggest that both stem and loop bases are important sources of phylogenetic information, although stem positions are prone to compensatory substitutions. Of the stem changes analyzed, only 27% destroy a base-pairing couplet; 73% maintain or restore base pairing.